3Q2 Roosevelt Wild Life Bulletin 



Brown Trout. Bean stated ('i6) that the brown trout is a native 

 of Europe, and that it has become acclimatized in many parts 

 of the United States. He said that it is very hardy and ranks as 

 one of the finest game fishes, and that it lives in clear, cold, rapid 

 streams, its food and habits being similar to the brook and rainbow 

 trouts'. He added, however, that since this fish grows to a much 

 larger size and preys upon the others, it should never be introduced 

 into waters already supplied with native trout. He further stated 

 that it withstands a higher summer temperature than the brook 

 trout, and has replaced that species in certain waters where the 

 surrounding forests have been largely cleared away. 



Embody indicates that the brown trout will live in water up to 

 83 degrees and possibly in " a little lower oxygen content " and 

 " where pollution is a little greater " than in the case of brook trout. 



W. C. Adams ('20) says that " in 1917, after four extraordinarily 

 hot days, there were found at the dam at Littleville [Massachusetts], 

 where the water was 84 degrees, 37 dead brown trout weighing 

 from one to five pounds eight ounces, the largest 27^ inches in 

 length. This occurred at a time when the river was unusually low. 

 In normal times the fish would have saved themselves by dropping 

 down to cooler water." 



This would suggest that 83 degrees of heat is somewhat too near 

 the danger line to be accepted as a standard of upper temperature 

 limit for the safety of brown trout, and especially if there is lower 

 oxygen content or pollution. 



Embody ('22) says: "It is believed that of the three trout the 

 brown trout is the most predacious and most destructive of other fish 

 and it is often stated if a stream is stocked with all three species 

 the browns will eventually exterminate the others. There are many 

 streams where brook trout have disappeared or become greatly 

 reduced in numbers a few years after the introduction of brown 

 trout, but it has in no case been proved that the brown trout has 

 caused the trouble. In fact there are streams in Tompkins County 

 where the brook trout and brown trout occur apparently in equal 

 numbers and have lived so for a number of years." 



" Often the upper part of a stream," he says, " is well suited to 

 brook trout while in the lower part browns only will survive. In 

 such cases an impassable dam or falls conveniently located will 

 make it possible to stock the lower part with browns without injur- 

 ing the brook trout fishing above." 



Concerning this fish, Nevin ('20) says : " We intend to increase 

 our capacit}^ and keep a much larger stock of brown trout in the 

 future than we have in the past, as the fry planted in our streams 

 have done exceptionally well. I do not find from observation that 

 the brown trout are any more destructive in the way of cannibalism, 

 of which they are accused, than any other variety of game fish." 



The present Avriter is emphatically opposed to the brown trout 

 in any waters where the brook trout exists or can be made to 

 exist. There are waters which have become unsuitable for brook 

 trout, in which brown trout have become established and aflford 



